Valliant vertical flue

3 May 2010
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United Kingdom
My plumber has installed a Vaillant ecotec plus 418 boiler. The vertical flue used does not utilise a cowl over the exhaust outlet, without a cowl over the top it would seem to allow rain or dust to fall into the pipe when the boiler is not on. This flue appears to be a standard Vaillant flu kit but is the arrangement ok? All other vertical flue's I have seen fitted appear to have a cowl fitted on top of the outlet pipe presumably to stop ingress from the atmosphere. Can an expert please advise, am I worrying unnecessarily about this? [Can't get access to makers technical team for advice] :confused:
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If you mean your installer has used a horizontal flue as a vertical option, its not correct and needs rectifying immediately.
A picture would be nice, to confirm what your saying.
The later Vaillant vertical terminals do have an open end.

Being a condensing boiler water is meant to go down the flue.
its fine, standard on all vaillant group flues now. rain won't do any harm, if anything it will help keep the condense ways clean and clear :D
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On mine the flue gas (inside pipe) is open to the sky. The outside combustion air pipe is protected from rain by a hat so it can only draw air from underneath. 2 years old.
Vaillant Vertical Flue
Thanks to all for your replies, you have put my mind at rest. :)
As long as your boiler has been installed by a Gas Safe installer and registered/notified with Gas Safe you should have nothing to worry about.

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